I thought a good way to start off my portal would be to write a simple HTML type of report using the DOS test suite I developed. This tests the network looking for machines exposed on the monitoring AND attack networks, and also detects routers and switches, firewalls etc. A HTML readout of the testbed setup would be a good place to start building and would be easy enough to get me started on porting all my code to the portal.
In fact, why not turn it into a fully-fledged topology view? Rather than just list computers and routers using text, why not draw them using icons? Then use colours to indicate their status. We could write out the network status in XML then view it using an interactive applet.